Scientists are advancing slowly toward one of the most audacious goals humans have ever set for themselves: creating artificial life. They've already accomplished some steps needed to construct a simple, single-celled organism that's capable of evolving and reproducing itself - basic requirements for life. While there are many difficulties, the difficulties don't keep researchers from trying to simulate life, if not create it from a blank slate. Steen Rasmussen, a physicist at the Los Alamos National Laboratory in New Mexico, heads a "Protocell Project." Its goal is to build lifelike artificial cells that are "self-reproducing and capable of evolution; self-containing, thereby possessing individual identity; self-sustaining in that they can maintain their complex structure."